Revert "Adds examples for extra subject identifiers"

It was accidentally committed to the develop branch by a tired developer.

This reverts commit 4daa687.

ob_v3p0/impl/recommended-practices.md

@@ -609,80 +609,3 @@ skills.
     ]
 }
 </pre>
-
-### Including additional recipient profile information
-
-Sometimes issuers want credentials to be shareable to audiences who are not
-capable of authenticating subjects via an identifier such as a DID. Many of
-these use cases may be served by including one or more email identifiers. (Only
-partial data is shown for clarity, for example omitting the `achievement` claim
-within `credentialSubject`.)
-
-<pre class="json example" title="Email identifier in credential subject">
-{
-    "credentialSubject": {
-        "id": "did:example:ebfeb1f712ebc6f1c276e12ec21",
-        "type": "AchievementSubject",
-        "identifier": [
-            {
-                "type": "IdentityObject",
-                "hashed": false,
-                "identityHash": "[email protected]",
-                "identityType": "emailAddress"
-            }
-        ]
-    }
-}
-</pre>
-
-If the known email address for the user is expected to no longer be a useful
-source of authentication, such as if the user loses access to a work or
-university email after leaving that organization (perhaps 6 months after
-graduation), an issuer may wish to provide additional identifying information,
-such as a name.
-
-<pre class="json example" title="Name identifier in credential subject">
-{
-    "credentialSubject": {
-        "id": "did:example:ebfeb1f712ebc6f1c276e12ec21",
-        "type": "AchievementSubject",
-        "identifier": [
-            {
-                "type": "IdentityObject",
-                "hashed": false,
-                "identityHash": "Albert Exampleton",
-                "identityType": "ext:name"
-            }
-        ]
-    }
-}
-</pre>
-
-Inclusion of additional personally identifiable information about the subject,
-especially with `"hashed": false`, reduces the potential anonymity of the
-subject. Those with whom the credential is shared may share it to others, who
-would be able to view this identifying information. While sharing typically
-passes through control of the subject/holder, different issuers may weigh the
-potential benefits of including this information against the risks of
-unauthorized disclosure.
-
-If issuers desire to include much more information about the subject in the
-credential, they may add the `Profile` type and include additional properties
-from Profile. The above approach using IdentityObject is expected to be more
-broadly usable, because displayers of `OpenBadgeCredentials` will expect this
-type of data. Additional data from `Profile` is not expected directly within
-`credentialSubject`, so it is less likely that displayers would build custom
-handling for these unexpected properties. An "advanced" view where users may
-review the JSON data directly may be included in some displayer products, in
-which case viewers would be able to review this information more directly.
-
-<pre class="json example" title="Given name and family name credential subject with Profile">
-{
-    "credentialSubject": {
-        "id": "did:example:ebfeb1f712ebc6f1c276e12ec21",
-        "type": ["AchievementSubject", "Profile"],
-        "givenName": "Albert",
-        "familyName": "Exampleton"
-    }
-}
-</pre>